Exceptional 18k (750 thousandths) and 14k (585 thousandths) yellow gold rectangular cutaway watch with two dials in very good condition, the upper dial showing the seconds and the lower showing the hours. In the middle, a window on the balance wheel is surrounded by rose-cut diamonds, surmounted by two opaque blue enamelled birds. The rest of the plate is black enamelled and engraved with flowers. The surround is decorated with probably fine half-pearls and underlined by an engraved Greek frieze. The ring is adjustable by a slide mechanism from size 53 to 61. The ring is engraved on each side with a Greek frieze and in the middle with floral motifs in the style of the 16th and 17th centuries. The bevelled glass is very slightly chipped. Anonymous work between 1780 and 1800. Manual mechanical movement with key (present). Access for setting and winding is via a remarkable sliding plate under the case back. Dimensions of the plate: 3 x 1.6 cm. Very good condition. Not functional. Gross weight: 17.6 g. Expert's note: Eighteenth-century watch rings in such good condition are rare. And those with a double dial even rarer. A few examples can be found in major museums, such as the Museum of Fine Arts in Boston, which has a German ring watch from the same period in its storeroom that has never been exhibited to the public.